> It isn't clear you can. An application using UDP is expecting message > boundaries to be preserved. That is a fundamental part of the semantics of > UDP. So if an application has sent three, 128 byte messages via UDP, the > receiving side is expecting to receive three, 128 byte messages, not one 384 > byte message. If the receiver can indeed deal with just one, 384 byte > message, that is what the sending side should have sent in the first place. > Ok i'm explaining it a bit more so no confusion about what i'm trying to achieve. In our application, we are send RTP(http://en.wikipedia.org/wiki/Real-time_Transport_Protocol) packets. These RTP packets have encoded voice data as their payload. When a voice communication occurs its quiet bandwidth consuming. Thousands of udp packets are transmitted in a matter of seconds. So when a client is in low bandwidth area, its more logical to send large udp packts with multiple rtp packets concatenated. Take for instance G729 codec has a 10ms frame. which is encoded as 10 bytes of voice data. every rtp packets has 12 bytes of header. its totally wasteful of bandwidth that to send only 10 bytes of voice data as a payload of 12 bytes of header. If 5 RTP frames are concatenated then we are transmitting 50 bytes with a single 12 byte header. then payload to header ratio is 50/12 which far less than 10/12. The more bigger packet we send the more this ratio increase and so our bandwidth consumption reduced. But there is also a trade off. the more frames we send in packet the quality of voice decreases slightly. After some testing we have come to conclusion that sending 10 packets in a single udp datagram is a optimum choice. We use our existing netfilter_queue app to encryption/obfuscation of voice data to escape certain firewall and telecom operators malpractices. For improving our service we have decided that we will increase our payload size. Problem is different SIP servers vary in their capability of repack RTP packets. some can do a lot but other's do not. we do not want to select a telephony server based on this property because lot of other variables are involved in the selection process. And for different services we use several Telephony platform. So we want our application to be capable of repack rtp packets so that we can use whatever telephony platforms we want without thinking about this. This way our service implementation will be more robust and will not create unnecessary dependencies. Thank you for your reply -- -aft -- To unsubscribe from this list: send the line "unsubscribe netfilter" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
